Biomedical subjects

S Katayama

Publications and source records attributed to S Katayama.

At least 235 records · Page 13Linked to original sources

PubMed1994

CAG expansions in a novel gene for Machado-Joseph disease at chromosome 14q32.1.

We have identified a novel gene containing CAG repeats and mapped it to chromosome 14q32.1, the genetic locus for Machado-Joseph disease (MJD). In normal individuals the gene contains between 13 and 36 CAG repeats, whereas most of the clinically diagnosed patients and all of the affected members of a family with the clinical and pathological diagnosis of MJD show expansion of the repeat-number (from 68-79). Southern blot analyses and genomic cloning demonstrates the existence of related genes. These results raise the possibility that similar abnormalities in related genes may give rise to diseases similar to MJD.

Adult↗

PubMed1994

Effect of heat shock on intracellular calcium mobilization in neuroblastoma x glioma hybrid cells.

The effect of heat shock on agonist-stimulated intracellular Ca2+ mobilization and the expression of heat shock protein 72 (hsp72) in neuroblastoma x glioma hybrid cells (NG 108-15 cells) were examined. Hsp72 was expressed at 6 h after heat shock (42.5 degrees C, 2 h), reached a maximum at 12 h, and decreased thereafter. Bradykinin-induced [Ca2+]i rise was attenuated to 28% of control by heat shock at 2 h after heat shock, and reversion to the control level was seen 12 h later. When the cells were treated with quercetin or antisense oligodeoxyribonucleotide against hsp72 cDNA, the synthesis of hsp72 was not induced by heat shock, whereas bradykinin-induced [Ca2+]i rise was abolished and the [Ca2+]i rise was not restored. Recovery from this stressed condition was evident when cells were stimulated by the Ca(2+)-ATPase inhibitor thapsigargin, even in the presence of either quercetin or antisense oligodeoxyribonucleotide. Inositol 1,4,5-trisphosphate (IP3) production was not altered by heat shock at 12 h after heat shock, whereas IP3 receptor binding activity was reduced to 45.3%. In the presence of quercetin or antisense oligodeoxyribonucleotide, IP3 receptor binding activity decreased and reached 27.2% of the control 12 h after heat shock. Our working thesis is that heat shock transiently suppresses the IP3-mediated intracellular Ca2+ signal transduction system and that hsp72 is involved in the recovery of bradykinin-induced [Ca2+]i rise.

Animals↗

PubMed1994

Enterotoxic activity of Klebsiella oxytoca cytotoxin in rabbit intestinal loops.

We examined the enterotoxicity of a Klebsiella oxytoca cytotoxin which is produced by K. oxytoca OK-1, a strain from a patient with antibiotic-associated hemorrhagic colitis. Injection of the cytotoxin into ligated ileal and colonic loops in rabbits caused the accumulation of fluid in the loops. The fluid was bloody in the ileal loops but not in the colonic ones. Histological examination revealed intense mucosal hemorrhage with erosion in the ileum, whereas no microscopic change was noted in the colon. The fluid accumulation was shown to be a dose-dependent response in both ileal and colonic loops. The amounts of the cytotoxin required for maximal fluid accumulation in ileal and colonic loops were 60 and 10 micrograms, respectively. Fluid accumulation was first noticeable in ileal loops 12 h and in colonic ones 5 h after the injection of these doses of the cytotoxin and then proceeded with time. When K. oxytoca OK-1, a cytotoxin-producing strain, was inoculated into the loops at doses of 1 x 10(8) and 5 x 10(9) CFU, similar fluid accumulation was observed. However, inoculation of K. oxytoca ATCC 13182, a non-cytotoxin-producing strain, at the same doses did not cause any change. These results suggest that the cytotoxin-producing strain of K. oxytoca is the causative organism of antibiotic-associated hemorrhagic colitis and that the toxin is the factor responsible for pathogenesis.

Animals↗

PubMed1994

Purification and characterization of Clostridium perfringens 120-kilodalton collagenase and nucleotide sequence of the corresponding gene.

Clostridium perfringens type C NCIB 10662 produced various gelatinolytic enzymes with molecular masses ranging from approximately 120 to approximately 80 kDa. A 120-kDa gelatinolytic enzyme was present in the largest quantity in the culture supernatant, and this enzyme was purified to homogeneity on the basis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme was identified as the major collagenase of the organism, and it cleaved typical collagenase substrates such as azocoll, a synthetic substrate (4-phenylazobenzyloxy-carbonyl-Pro-Leu-Gly-Pro-D-Arg [Pz peptide]), and a type I collagen fibril. In addition, a gene (colA) encoding a 120-kDa collagenase was cloned in Escherichia coli. Nested deletions were used to define the coding region of colA, and this region was sequenced; from the nucleotide sequence, this gene encodes a protein of 1,104 amino acids (M(r), 125,966). Furthermore, from the N-terminal amino acid sequence of the purified enzyme which was found in this reading frame, the molecular mass of the mature enzyme was calculated to be 116,339 Da. Analysis of the primary structure of the gene product showed that the enzyme was produced with a stretch of 86 amino acids containing a putative signal sequence. Within this stretch was found PLGP, the amino acid sequence constituting the Pz peptide. This sequence may be implicated in self-processing of the collagenase. A consensus zinc-binding sequence (HEXXH) suggested for vertebrate Zn collagenases is present in this bacterial collagenase. Vibrio alginolyticus collagenase and Achromobacter lyticus protease I showed significant homology with the 120-kDa collagenase of C. perfringens, suggesting that these three enzymes are evolutionarily related.

Amino Acid Sequence↗

PubMed1994

Felodipine therapy may not alter glucose and lipid metabolism in hypertensives. Felodipine Multicenter Prospective Study Group in Japan.

The effects of long-term monotherapy with felodipine, a calcium antagonist, on blood pressure, glucose tolerance, and serum lipid profiles were prospectively investigated in 51 hypertensive patients: 13 with normal glucose tolerance and 38 with glucose intolerance. The levels of plasma glucose, serum lipids, and glycosylated hemoglobin A1c were determined before and during long-term (7.5 +/- 0.5 months; range, 6 to 9 months) therapy with felodipine. A 75-g oral glucose tolerance test was performed before and during long-term felodipine therapy. Significant decreases in both systolic and diastolic blood pressures in both patient groups were maintained during the therapy. Neither fasting nor post-glucose load venous plasma glucose levels were altered in either group of patients, and no patients with normal glucose tolerance developed diabetes mellitus during the study. Serum lipid levels did not change significantly in either group of patients except for significant decreases in high-density lipoprotein cholesterol and apolipoprotein A-I in the group with normal glucose tolerance tests, but those changes remained within the normal range. Furthermore, neither serum lipid nor apolipoprotein levels were altered, even in patients with hypercholesterolemia (total cholesterol levels, > 5.69 mmol/L = 220 mg/dL). These results suggest that long-term therapy with felodipine may not alter glucose and lipid metabolism in hypertensive patients, and felodipine appears to be useful as an antihypertensive agent for hypertensive patients with either dyslipidemia or impaired glucose metabolism.

Analysis of Variance↗

PubMed1994

Evidence against a role of insulin in hypertension in spontaneously hypertensive rats. CS-045 does not lower blood pressure despite improvement of insulin resistance.

Hyperinsulinemia resulting from peripheral insulin resistance has been demonstrated both in spontaneously hypertensive rats (SHR) and in humans with essential hypertension. A new class of antidiabetic drugs, thiazolidinediones, which can improve insulin resistance, may be able to lower not only blood glucose levels but also blood pressure. The present study was therefore designed to clarify the proportion of SHR that are glucose intolerant and to observe the effect on blood pressure of CS-045 (troglitazone) administered at 70 mg/kg per day for 2 weeks to male SHR (n = 13). Among 67 male 8-week-old SHR, 74.6% were glucose intolerant and hyperinsulinemic. Systolic blood pressure did not correlate with plasma glucose or insulin levels before or after glucose loading. Treatment with CS-045 improved insulin resistance, as evidenced by a smaller area under the curve of plasma glucose and insulin levels in response to glucose loading. However, systolic blood pressure was not altered. When the data were reanalyzed according to the presence or absence of glucose intolerance before the treatment, blood pressure in the treated group was the same as in controls despite significant improvement in steady-state plasma glucose levels. These results suggest that hyperinsulinemia and/or insulin resistance may not be involved in the development or maintenance of hypertension in SHR, which is in contrast to models of hypertension such as obese Zucker rats or fructose-fed rats.

Animals↗

PubMed1994

Marine natural products. XXXIII. Theonellapeptolide IId, a new tridecapeptide lactone from the Okinawan marine sponge Theonella swinhoei.

Following the characterization of theonellapeptolides Ia-Ie (2-6), another new tridecapeptide lactone named theonellapeptolide IId (1) was isolated from the Okinawan marine sponge Theonella swinhoei. The structure of 1 has been determined on the bases of chemical and physicochemical examinations which included an HPLC-CD combined analysis of the amino acid composition. Theonellapeptolide IId (1) prevented fertilization of the sea urchin Hemicentrotus pulcherrimus at the concentration of 25 micrograms/ml or greater but did not affect early embryonic development of fertilized eggs up to the gastrula stage.

Amino Acid Sequence↗

PubMed1994

Possible role of protein kinase C in regulation of flagellar motility and intracellular free Ca2+ concentration of fowl spermatozoa.

The presence and possible role of protein kinase C in the regulation of fowl sperm functions were investigated. Immunoblot analysis of sperm extract using antibody to protein kinase C revealed a crossreacting protein of approximately 80 kDa. As the concentration of the protein kinase C activators N-(6-phenylhexyl)-5-chloro-1-naphthalenesulfonamide (SC-9) or 1-oleoyl-2-acetylglycerol (OAG) was increased, the motility of intact spermatozoa at 30 degrees C was reduced. However, this inhibition of motility was reversed by reducing the concentrations of activators. Even in the presence of 1 mmol CaCl2 l-1, the addition of SC-9 and OAG inhibited the motility of intact spermatozoa. In contrast, the motility of demembranated spermatozoa was not inhibited by the addition of SC-9 or OAG at 30 degrees C. However, the addition of 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), a protein kinase C inhibitor, did not appreciably affect the motility of either intact or demembranated spermatozoa at 30 degrees C. At 40 degrees C, both intact and demembranated spermatozoa were almost immotile in the presence or absence of the activators or inhibitor. Intracellular free Ca2+ concentrations, measured by means of a fluorescent Ca2+ indicator, fura-2, gradually increased after the addition of SC-9 and OAG, but no changes were observed in H-7-treated spermatozoa. These results suggest that endogenous protein kinase C is present in the cytoplasmic matrix or the membrane, but is not retained in the axoneme, and that the activation of this enzyme may contribute to a decrease in the flagellar movement of fowl spermatozoa.

Animals↗

PubMed1994

[The effect of age and disease on the MR imaging T2 low signal intensity area in the cerebral cortex].

We retrospectively studied magnetic resonance (MR) images of the brain in 139 patients (16 cases of Alzheimer's disease, 8 cases of Parkinson's disease, 53 cases of multiple cerebral infarct, 33 cases of other central nervous diseases, and 29 cases of peripheral neuropathy) between the age of 6 and 85 years old with a mean age of 60.6 +/- 18.5 to examine the appearance of T2 low signal intensity areas (T2CLIA) in the cerebral cortex. Motor, occipital, sensory or other cortices were evaluated with long repetition time/echo time (TR/TE) spin-echo sequences and staged into three grades in the motor cortex: none, partial, and whole; and two grades in the others: none or present. In general, T2CLIA was not seen in any cortex in patients less than 50 years old, then after 50 years old T2CLIA increased with age. Over 70 years of age T2CLIA appeared in 50.9% of patients in the whole motor cortex, 88.7% in either whole or partial motor cortex, 47.2% in the occipital cortex, and 20.8% in the sensory cortex. T2CLIA was not observed in other cortices. The incidence of T2CLIA appearance in the motor cortex was significantly higher in all central nervous diseases than in cases of peripheral neuropathy over 70. T2-CLIA showed a correlation with temporal lobe atrophy and white matter lesions in the motor cortex. In the sensory cortex, T2CLIA correlated with white matter lesions. These results suggest that T2-CLIA may correlate with age or accumulation of nonheme iron in the cortex associated with central nervous diseases.

Adolescent↗

PubMed1994

[Treatment modalities and hypothalamo-pituitary-adrenal (HPA) axis suppression in Japanese patients with asthma].

We examined HPA axis function using a short tetracosactrin test in 94 asthmatics treated with three different modalities. The first group, (B + S), consisted of 41 patients taking BDP (910 +/- 320 micrograms, daily) plus a short term burst of oral steroids (20-40 mg daily, 3-7 days/course, 1-18 courses/year). The second group, (B + R), consisted of 19 patients taking BDP (1076 +/- 410 micrograms, daily) plus continuous oral steroids (2.5-20 mg/day for 1.8-24 years). The third group, (B alone), consisted of 34 patients taking BDP only (615 +/- 258 micrograms, daily). All patients had been inhaling BDP for more than 1 year. The rise in cortisol in response to tetracosactrin in B + S, B + R, and B alone was 12 +/- 4.3 micrograms/dl, 7.0 +/- 5.0 micrograms/dl and 14 +/- 4.5 micrograms/dl, respectively, and achieved cortisol was 21 +/- 4.5 micrograms/dl, 12 +/- 7.2 micrograms/dl and 23 +/- 4.2 micrograms/dl;, respectively. Both values were significantly lower in the B + R group than in either B + S or B alone. However, there was no difference between B + S and B alone, although the BDP dose was significantly larger in the B + S group. Significant HPA axis suppression (rise in cortisol < 7 micrograms/dl and achieved cortisol < 18 micrograms/dl) was seen in 7 patients. Although HPA axis suppression was more frequently seen in B + R (10/19), no significant difference was seen between B + S and B alone (4/41 and 1/34, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗

PubMed1994

[A case of hemangioblastoma in the thalamus].

Supratentorial hemangioblastoma is encountered very rarely. About 80 cases in all have been reported. The authors present a case of supratentorial hemangioblastoma in the thalamus with gradually enlarging cysts. The patient was a 45-year-old man with complaints of left hemiparesis and headache. Computed tomographic scans of the brain showed a cystic mass with mural nodule in the right thalamus. Left vertebral angiography demonstrated a vascular tumor fed by a thalamogeniculate artery. A right temporo-parietal craniotomy was performed and the tumor was totally resected through the transcortical approach. The histological diagnosis was hemangioblastoma. Post-operative course was good except for a minor complication of the left lower quadrant homonymous hemianopsia and left hemiparesis which had disappeared at the time of discharge.

Hemangioblastoma↗

PubMed1994

[Middle cerebral artery occlusion with unilateral moyamoya like vessels and with ruptured anterior cerebral artery aneurysm--its relation to the antiphospholipid antibody syndrome].

We report a case of right middle cerebral artery occlusion associated with ipsilateral basal moyamoya like vessels and ruptured anterior cerebral artery aneurysm. A 59-year old man suddenly developed a consciousness disturbance and was brought to our hospital by ambulance. On admission, computed tomography (CT) of the head revealed a diffuse dense high-density lesion in the basal cistern and in the bilateral sylvian fissures, and a round homogeneous high-density area in the interhemispheric fissure. Subsequent angiography showed a large anterior cerebral artery aneurysm and occlusion of the right middle cerebral artery with moyamoya-like vessels. We made a diagnosis of subarachnoid hemorrhage due to aneurysm rupture. An emergency bifrontal free bone craniotomy was performed, utilizing the interhemispheric approach and the neck of the aneurysm was clipped. On the 68th postoperative day the patient was ambulatory and discharged from the hospital. Hemodynamic stress was thought to be the main cause of the anterior cerebral artery aneurysm. Because the laboratory data on admission included a false-positive serological test for syphilis, we tested the patient for antiphospholipid antibodies, and repeatedly found anticardiolipin antibody in the patient's serum. The antiphospholipid antibody syndrome may have been responsible for the occlusion of the middle cerebral artery, in this patient and we think that testing for serum antiphospholipid antibodies is important in occlusive cerebral artery disease, especially in moyamoya disease or when moyamoya-like vessels are present.

Aneurysm, Ruptured↗

PubMed1994

[Möbius syndrome with crossed total hemiatrophy--a case report].

The patient was a 26-year-old male who was noted to have asymmetry on the face, upper limbs, and trunk, and who showed no pursuit eye movements and no changes in the facial expression from birth. The patient developed transient global amnesia and was hospitalized. Neurological examination established atrophy of the right face, and left trunk involving the upper limb, and bilateral oculomotor and abducens nerve palsy. In auditory brainstem response, waves III to V were bilaterally obscured, and the blink reflex disclosed disturbances of peripheral facial nerve and the brainstem, suggesting developmental abnormalities of the facial motor nucleus. Contralateral R1 was also recorded in the blink reflex, and crossed trigeminofacial pathway was suspected. Möbius syndrome is associated with various muscle and skeletal abnormalities, but the coexistence of crossed total hemiatrophy has not been reported. We think that our case might be the first case of Möbius syndrome with total hemiatrophy.

Abnormalities, Multiple↗

PubMed1994

[A case of Fisher's syndrome with upbeat nystagmus].

We reported a case of Fisher's syndrome with upbeat nystagmus. The syndrome manifested itself with the appearance of diplopia and ataxic gait preceded by cold-like symptoms. Although slight blephaloptosis, marked bilateral upward gaze palsy, and restricted abduction of the right eye were observed, light reflexes and Bell's phenomenon were normal. A slight decrease in the muscular power of the distal extremities, bilateral fingertip dysesthesia, and diminished sensation of vibration were observed. All muscle stretch reflexes were absent, and no pathologic reflexes were noted. Truncal ataxia and incoordination were observed. The cerebrospinal fluid showed albumino-cytologic dissociation. Upbeat nystagmus in five directions of gaze was recorded on the EOG, the smooth pursuit eye movement showed a staircase pattern, and dysmetria was present in the saccadic eye movement. The caloric test elicited a satisfactory response, but the visual suppression test produced poor suppression. Taken altogether, the test results suggest that the responsible lesions in this case were not only peripheral but also central, extending from the midbrain to the tegmentum pontis and the vestibulocerebellum.

Adolescent↗

PubMed1994

[A case of malignant syndrome with leukoencephalopathy due to cocaine abuse].

We report a rare case of malignant syndrome with leukoencephalopathy due to cocaine abuse. The patient was a 22-year-old man. After nasally ingesting 4.2 g of cocaine, he developed coma, high grade fever of 39 degrees C, excessive sweating, muscular rigidity, and elevation of CK to 61,240 mU/ml. Although these symptoms improved in about 2 weeks, diffuse low density area of the cerebral white matter was observed in CT scan, and T2-weighted MRI revealed a high signal intensity area. Since disorientation and abnormal behavior appeared on the 24th hospital day after a lucid interval, sulpiride and haloperidol were administered. The patient again had fever, akinetic mutisn, severe muscular rigidity and excessive sweating. This patient has malignant syndrome associated with a wide-ranging lesion of the cerebral white matter as a result of cocaine abuse. And then antipsychotic drugs were administered for mental symptoms that recurred after a lucid interval, and second bouts of neuroleptic malignant syndrome occurred. There have been only a few reports on malignant syndrome due to cocaine, and there have been no reports on leukoencephalopathy due to cocaine or malignant syndrome.

Adult↗

PubMed1994

Rhythms in the central nervous system and 1/f fluctuations of the heart rate.

We have developed a system to analyze heart rate variability (HRV) (power spectral array of the HRV) during 24 h ambulatory electrocardiographic monitoring. Several rhythms (circadian and several ultradian rhythms) were observed in the power spectral array of the heart rates and 1/f-like fluctuations in the log-log scaled heart rate power spectrum. The circadian change of the heart rate is closely related to the body temperature rhythm. The 90 min rhythm of HRV during sleep was suspected to be produced by the sleep cycle (REM/NREM) and the lower frequency peak of the HRV was coherent with oscillation in amplitude modulated respiration. These circadian and ultradian rhythm as assessed by heart rate variability exist both in normal subjects and in patients with autonomic failure. The power of the high frequency band decreases in subjects with autonomic failure. The power of low frequency components increases during periodic breathing or Cheyne-Stokes respiration. Log-log scaled analysis of the power spectrum of HRV disclosed that the slope of the HRV is markedly modulated by the range of the frequency applied for the least square regression line analysis. The increased power that might be produced by periodic breathing and decreased power in patients with autonomic failure might strongly modulate the slope of the log-log scaled HRV. It is concluded that the power spectral array of the HRV during 24 h period is useful in the detection of circadian and ultradian rhythm, and log-log scaled power spectra might be useful in the overall integration of the heart rate dynamics produced by the central nervous system. The several rhythm factors that might be produced by the central nervous system might modulate 1/f fluctuations of the HRV.

Body Temperature↗

PubMed1994

[Antiplatelet therapy in patients with cerebral thrombosis at the chronic phase--assessment of its effect on coagulation and fibrinolytic parameters].

We studied the effect of antiplatelet therapy not only on the secondary prevention of stroke but also on the suppression of vascular damages in patients with cerebral thrombosis at the chronic phase. We measured von Willebrand factor (vWF) as a marker for the endothelial system, and coagulation and fibrinolytic parameters in addition to platelet functions. The platelet aggregation and markers for platelet activation were monitored for the adequate inhibition of platelets. Twenty-one patients were treated with 200 mg ticlopidine. 9 patients with 100 mg ticlopidine and 60-150 mg acetylsalicylic acid, and 18 patients with 200 mg cilostazol daily. The mean duration of follow up was 8.4 +/- 3.0 months. A patient was attacked by a recurrent stroke, but no fatal vascular events occurred during the period. A significant decrease was observed in the collagen- and ADP-induced platelet aggregation and markers for platelet activation such as platelet factor 4 (PF4) and beta-thromboglobulin (beta TG) by the antiplatelet therapy. In addition, the activities of coagulation factor VIII (FVIII) and vWF, markers for vascular damages, showed a significant decrease. The results suggest that the antiplatelet therapy could ameliorate the vascular damage through the inhibition of platelet function. Moreover, thrombin-antithrombin III complex (TAT) and alpha 2-plasmin inhibitor-plasmin complex (PIC), markers for the activation of coagulation and fibrinolytic systems, decreased significantly, suggesting that the treatment inhibits the activation of coagulation and fibrinolytic systems induced by the platelet activation. The activities of FVIII and vWF decreased significantly when the level of beta TG or that of PF4 lowered sufficiently by the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1994

[Klinefelter syndrome accompanied by hypoplasia of the bilateral internal carotid arteries--a case report].

The patient was a 31-year-old male who was admitted to our hospital due to slowly progressive weakness of the right upper limb and both lower limbs. Physical examination showed a tall stature, gynecomastia, feminine pubic hair, small penis and small testis. His intellectual function on the Kohs-cubic test scored 85, on the WAIS scored performance 80, verbal 74 and full scale 78. He showed BE mixed type in YG personality test and neurotic in CMI. No abnormalities were observed except for severe weakness of the right upper limb, moderate weakness of the bilateral lower limbs and hypalgesia in the limbs. Clinical laboratory tests revealed low blood and urinary testosterone levels, and a high blood gonadotropin level. Cytogenetic studies showed a 47, XXY karyotype. On neuroradiological examinations, there were small bilateral carotid canals in CT scan and multiple long T2 lesions in MRI. Angiography showed hypoplasia of the bilateral internal carotid arteries and dilatation of the bilateral vertebral arteries. The results of activity measurements of affected limbs using actigraph indicated that a conversion type hysteria had resulted in weakness of the limbs. There is no report of Klinefelter syndrome accompanied by the hypoplasia of bilateral internal carotid arteries, and the condition is considered to be extremely rare.

Adult↗